TWI791554B - Curable organopolysiloxane composition and optical semiconductor device - Google Patents

Abstract

A curable organopolysiloxane composition that can be used as a sealant or a bonding agent for optical semiconductor elements and comprises at least the following components: (A) an alkenyl-containing organopolysiloxane that comprises constituent (A-1) of an average compositional formula and constituent (A-2) of an average compositional formula; (B) an organopolysiloxane that contains silicon-bonded hydrogen atoms and comprises a constituent (B-1) containing at least 0.5 wt.% of silicon-bonded hydrogen atoms and represented by an average molecular formula, constituent (B-2) containing at least 0.5 wt.% of silicon-bonded hydrogen atoms and represented by an average compositional formula, and, if necessary, constituent (B-3) of an average molecular formula; (C) an adhesion promoter; and (D) a hydrosilylation-reaction catalyst. The composition can form a cured body that possesses long-lasting properties of light transmittance and bondability, and relatively high hardness.

Description

Curable organopolysiloxane composition and optical semiconductor device

The present invention relates to a curable organopolysiloxane composition, and an optical semiconductor device having an optical semiconductor element sealed and/or bonded by a cured body of the aforementioned composition.

In an optical semiconductor device having an optical semiconductor element such as a photocoupler, a light emitting diode, a solid-state image pickup element, or the like, a curable organopolysiloxane composition is used for sealing and/or bonding an optical semiconductor element. It is desirable that the cured body of such compositions neither absorb nor scatter light emitted or received from the semiconductor element. Furthermore, in order to improve the reliability of the optical semiconductor device, it is desirable that the cured body does not discolor or reduce bonding strength.

Japanese Unexamined Patent Application Publication (hereinafter referred to as "Kokai") No. 2006-342200 discloses a curable organopolysiloxane composition capable of forming a cured body with high hardness and high light transmission . However, cured bodies resulting from such compositions may be easily damaged during manufacture or use of optical semiconductor devices, or may be easily delaminated from optical semiconductor elements or packages for such elements.

Publication No. 2007-63538 and Publication No. 2008-120843 disclose curable organopolysiloxane compositions that can form cured bodies with excellent impact resistance properties. However, since such cured bodies are often yellowed over time, they are not suitable for sealing or bonding optical semiconductor elements of optical semiconductor devices intended to be used at high temperatures for a long time.

Publication No. 2012-12434 discloses a curable organopolysiloxane composition that can form a cured body with durable light transmission and bondability and relatively high hardness. However, these existing solutions for die attach have the problem of causing pad contamination, thus resulting in poor wire-to-pad bonding. Failure to bond the wires to the pads destroys electrical conductivity and causes the package itself to fail.

An object of the present invention is to provide a curable organopolysiloxane composition which can form a substantially transparent cured body which has durable light transmission and bondability , also provides more reliable packaging through low pad contamination. Another object is to provide an optical semiconductor device with excellent reliability and performance.

The curable organopolysiloxane composition of the present invention comprises at least the following components: (A) alkenyl-containing organopolysiloxane comprising 15 to 35 wt.% of component (A-1) and 65 to 85 wt.% of component (A-2), wherein component (A-1) contains organopolysiloxane with the following average composition formula: (R ¹ ₃ SiO _1/2)a (R ¹ ₂ SiO _2/2 ) _b (R ¹ SiO _3/2 ) _c (SiO _4/2 ) _d wherein R ¹ represents phenyl, methyl, or alkenyl having 2 to 10 carbon atoms; 0.4 to 50 mol % of all R ¹ groups It is an alkenyl group having 2 to 10 carbon atoms; the methyl group constitutes 90 mole % or more of the sum of the methyl group and phenyl group contained in ^R1 ; "a", "b", "c", and "d" is a number satisfying the following conditions: 0 ≤ a ≤ 0.05; 0.9 ≤ b ≤ 1; 0 ≤ c ≤ 0.03; 0 ≤ d ≤ 0.03; and a+b+c+d = 1; Composition (A-2) Organopolysiloxanes comprising the following average composition formula: (R ² ₃ SiO _1/2)e (R ² ₂ SiO _2/2 ) _f (R ² SiO _3/2 ) _g (SiO _4/2 ) _h (HO _1/2 ) _i wherein R represents phenyl, methyl, or alkenyl having 2 to 10 carbon atoms; 5 ^to 10 mole % of all ^R groups are alkenyl having 2 to 10 carbon atoms ; The methyl group constitutes 90 mole % or more of the sum of the methyl group and phenyl group contained in ^R2 ; "e", "f", "g", "h", and "i" meet the following conditions Numerical: 0.4 ≤ e ≤ 0.6; 0 ≤ f ≤ 0.05; 0 ≤ g ≤ 0.05; 0.4 ≤ h ≤ 0.6; 0.01 ≤ i ≤ 0.05; and e+f+g+h = 1; (B) organopolysiloxane An alkane containing silicon-bonded hydrogen atoms and comprising 80 to 100 wt.% of component (B-1), 0 to 20 wt.% of component (B-2), and 0 to 10 wt.% of component ( B-3); the proportions of each of (B-1), (B-2), and (B-3) are chosen so that they add up to 100 wt.%, and in amounts such that each 1 Moles of silicon-bonded hydrogen atoms in component (B) in the range of 0.5 to 2.0 moles of the total alkenyl content in component (A), wherein component (B-1) comprises an organopolysiloxane an organopolysiloxane containing at least 0.5 wt.% of silicon-bonded hydrogen atoms and represented by the following average molecular formula: R ³ ₃ SiO (R ³ ₂ SiO) _j (R ³ H SiO) _k SiR ³ ₃ wherein R ³ represents phenyl or methyl; methyl constitutes 90 mole percent or more of all groups contained in R ³ ; "j" is a number ranging from 0 to 35; and "k" is 1 A number ranging from 0 to 100; Ingredient (B-2) comprises an organopolysiloxane containing at least 0.5 wt.% of silicon-bonded hydrogen atoms and represented by the following average composition formula: ( HR ⁴ ₂ SiO _1/2)l (R ⁴ ₃ SiO _1/2 ) _m (R ⁴ ₂ SiO _2/2 ) _n (R ⁴ SiO _3/2 ) _o (SiO _4/2 ) _p (R ⁵ O _{1 /2} ) _q wherein R ⁴ represents phenyl or methyl; methyl constitutes 90 mole % or more of all groups contained in R ⁴ ; R ⁵ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms ;"l", "m", "n", "o", "p", and "q" are numbers satisfying the following conditions: 0.4 ≤ l ≤ 0.7; 0 ≤ m ≤ 0.2; 0 ≤ n ≤ 0.05; 0 ≤ o ≤ 0.5; 0.3 ≤ p ≤ 0.6; 0 ≤ q ≤ 0.05; and l+m+n+o+p = 1; Ingredient (B-3) is an organopolysiloxane represented by the following average molecular formula: HR ⁶ ₂ SiO (R ⁶ ₂ SiO) _r SiR ⁶ ₂ H wherein R ⁶ represents phenyl or methyl; methyl constitutes at least 90% of all groups contained in R ⁶ ; and "r" ranges from 10 to 100 Numbers within the range; (C) adhesion promoter in an amount of 0.1 to 5 parts by weight per 100 parts by weight of the sum of components (A) and (B); and (D) hydrosilylation catalyst in an amount of sufficient to cure the composition.

The composition of the present invention may further have (E) fumed silica, which has a BET specific area of 20 to 200 m ² /g, and is based on 100 parts by weight of component (A) to The sum of (D) is added in an amount of 1 to 10 parts by weight.

When the composition of the present invention is cured, it forms a substantially optically transparent cured body having a D-type durometer hardness in the range of 30 to 70 according to JIS K 6253, and which is suitable for use as a material for sealing or joining Reagent for optical semiconductor components (especially light-emitting diodes).

The optical semiconductor device of the present invention is characterized by having an optical semiconductor element sealed and/or bonded using a cured body of the aforementioned composition. Invention effect

The curable organopolysiloxane composition of the present invention is characterized by forming a cured body with durable light transmission and bondability, and relatively high hardness. The optical semiconductor device of the present invention is characterized by excellent reliability achieved in part by reducing wire bond failures.

Component (A) is the main component of the composition of the present invention, and it comprises an alkenyl-containing organopolysiloxane composed of the following components (A-1) and ( A-2) composed of.

Component (A-1) is used to improve the handleability of the composition and the mechanical strength of the cured body. This component contains organopolysiloxanes with the following average composition formula: (R ¹ ₃ SiO _1/2)a (R ¹ ₂ SiO _2/2 ) _b (R ¹ SiO _3/2 ) _c (SiO _4/2 ) _d wherein R ¹ represents phenyl, methyl, or alkenyl having 2 to 10 carbon atoms. The alkenyl group of R ¹ may be represented by vinyl, allyl, butenyl, pentenyl, or hexenyl. Vinyl is preferred in view of reactivity and ease of synthesis. However, 0.4 to 50 mol % of all ^R groups are alkenyl. This is because if the content of alkenyl groups is below the suggested lower limit, the cured body of the composition will have low mechanical strength, and if, on the other hand, the content of alkenyl groups exceeds the suggested upper limit, the cured body will become brittle. In addition, when the sum of the methyl group and phenyl group of ^R1 is set to 100%, the methyl group should constitute 90 mol% or more. This is because if the content of the methyl group is lower than the recommended lower limit, the cured body of the composition may easily acquire color at high temperature. In addition, in the above formula, "a", "b", "c" and "d" represent the value of the ratio of siloxane structural units, and satisfy the following conditions: 0 ≤ a ≤ 0.05; 0.9 ≤ b ≤ 1; 0 ≤ c ≤ 0.03; 0 ≤ d ≤ 0.03; and a+b+c+d = 1. If the value of "a" exceeds the recommended upper limit, this will result in a significant decrease in the viscosity of the ingredient. This would thus impair the handleability of the composition and make the ingredients volatile, or would reduce the weight of the composition during curing and reduce the hardness of the cured body. On the other hand, if the values of "c" and "d" exceed the suggested upper limits, this will increase the viscosity of the composition and will impair the handleability of the composition, or will cause the cured body to become unduly brittle. The value of "b" is determined by the values of "a", "c" and "d". However, if the value of "b" is lower than the recommended lower limit, it will not be able to impart the desired viscosity to the composition or impart the required hardness or mechanical strength to the cured body. Component (A-1) may have a linear, cyclic, partially cyclic, or partially branched molecular structure. This ingredient is liquid at 25°C. The viscosity of this component should be in the range of 3 to 1,000,000 mPa·s, preferably 5 to 50,000 mPa·s at 25°C. If the viscosity is below the suggested lower limit, this will reduce the mechanical strength of the cured body, and on the other hand, if the viscosity exceeds the suggested upper limit, this will impair the handleability of the composition.

Ingredient (A-1) can be represented by an organopolysiloxane represented by an average composition formula given below, wherein Vi represents a vinyl group, Me represents a methyl group, and Ph represents a phenyl group. (ViMe ₂ SiO _1/2 ) _0.012 (Me ₂ SiO _2/2 ) _0.988 (ViMe ₂ SiO _1/2 ) _0.007 (Me ₂ SiO _2/2 ) _0.993 (Me ₃ SiO _1/2 ) _0.007 (Me ₂ SiO _{2 /2} ) _0.983 (MeVi SiO _2/2 ) _0.010 (Me ₃ SiO _1/2 ) _0.01 (MeVi SiO _1/2 ) _0.01 (Me ₂ SiO _2/2 ) _0.96 (Me SiO _3/2 ) _0.02 (ViMe ₂ SiO _1/2 ) _0.005 (Me ₂ SiO _2/2 ) _0.895 (MePh SiO _2/2 ) _0.100

In addition, component (A-1) can be represented by organopolysiloxane represented by the average molecular formula given below, and Vi and Me are the same as defined above. (MeVi SiO _2/2 ) ₃ (MeVi SiO _2/2 ) ₄ (MeVi SiO _2/2 ) ₅

Component (A-2) is an organopolysiloxane used to impart hardness and mechanical strength to the cured body of the composition. This composition is represented by the following average composition formula: (R ² ₃ SiO _1/2)e (R ² ₂ SiO _2/2 ) _f (R ² SiO _3/2 ) _g (SiO _4/2 ) _h (HO _{1/2 2} ) _i

In this formula, R ² represents phenyl, methyl, or alkenyl having 2 to 10 carbon atoms. The alkenyl group of ^R2 can be represented by vinyl, allyl, butenyl, pentenyl, or hexenyl. Vinyl is preferred in view of reactivity and ease of synthesis. However, 5 to 10 mol % of all ^R groups are alkenyl. This is because if the content of alkenyl groups is below the suggested lower limit, the cured body of the composition will have low hardness and mechanical strength, and on the other hand, if the content of alkenyl groups exceeds the suggested upper limit, the cured body will become brittle. In addition, when the sum of the methyl group and phenyl group of R ² is set as 100%, the methyl group should constitute 90 mol% or more. This is because if the content of methyl groups is lower than the recommended limit, the cured body of the composition may easily acquire color at high temperature. In addition, in the above formula, "e", "f", "g", "h", and "i" represent the ratio of the siloxane structural unit to the hydroxyl group, and satisfy the following conditions: 0.4 ≤ e ≤ 0.6 ;0 ≤ f ≤ 0.05; 0 ≤ g ≤ 0.05; 0.4 ≤ h ≤ 0.6; 0.01 ≤ i ≤ 0.05; and e+f+g+h = 1. If the value of "e" is lower than the recommended lower limit, this will reduce the mechanical strength of the cured body, and on the other hand, if the value of "e" exceeds the recommended upper limit, this will not impart sufficient hardness to the cured body. If the value of "f" exceeds the recommended upper limit, it will not be able to impart sufficient hardness to the cured body. If the value of "g" exceeds the recommended upper limit, this will reduce the mechanical strength of the cured body. If the value of "h" is lower than the recommended lower limit, it will not be able to impart sufficient hardness to the cured body, and on the other hand, if the value of "h" exceeds the recommended upper limit, the dispersibility of the components in the composition will be impaired, and It will reduce the mechanical strength of the cured body of the composition. Finally, in order to provide compositions with good joinability, it is important to keep the value of "i" within the recommended range. If the value of "i" is below the suggested lower limit, it will not be able to provide a composition with the desired bonding properties, and on the other hand, if the value of "i" exceeds the suggested upper limit, this will impair the availability of the ingredient in the composition. dispersion, and will not allow to impart the desired mechanical strength and bonding properties to the cured body of the composition. Ingredient (A-2) may have a branched or network molecular structure. There is no particular restriction on the viscosity of this ingredient at 25°C, and it may be liquid or solid, provided it is miscible with ingredient (A-1).

Ingredient (A-2) can be represented by organopolysiloxane represented by the average composition formula given below, wherein Vi, Me, and Ph are the same as defined above. (ViMe ₂ SiO _1/2 ) _0.10 (Me ₃ SiO _1/2 ) _0.33 (SiO _4/2 ) _0.57 (HO _1/2 ) _0.03 (ViMe ₂ SiO _1/2 ) _0.13 (Me ₃ SiO _1/2 ) _0.35 (SiO _4/2 ) _0.52 (HO _1/2 ) _0.02 (ViMePh SiO _1/2 ) _0.10 (Me ₃ SiO _1/2 ) _0.45 (SiO _4/2 ) _0.45 (HO _1/2 ) _0.03 (ViMe ₂ SiO _{1 /2} ) _0.09 (Me ₃ SiO _1/2 ) _0.31 (SiO _4/2 ) _0.60 (HO _1/2 ) _0.04 (ViMe ₂ SiO _1/2 ) _0.10 (Me ₃ SiO _1/2 ) _0.40 (SiO _4/2 ) _0.50 (HO _1/2 ) _0.03

It is recommended that component (A) contain 15 to 35 wt.% of ingredient (A-1) and 65 to 85 wt.% of ingredient (A-2), and preferably 20 to 30 wt.% of ingredient (A -1) and 70 to 80 wt.% of ingredient (A-2). If the content of component (A-1) exceeds the recommended upper limit, it will not be able to impart the desired hardness and mechanical strength to the cured body of the composition, and on the other hand, if the content of component (A-1) is lower than the recommended lower limit, it will Impairs the handleability of the composition and imparts brittleness to the cured body.

If the composition can finally be prepared in a state of high uniformity, there is no need to premix the components (A-1) and (A-2) of the component (A). From the standpoint of good handleability, component (A) should be liquid at 25°C and have a viscosity in the range of 100 to 5,000,000 mPa·s, preferably 500 to 100,000 mPa·s.

Component (B) is used in the composition as a crosslinking agent. It comprises an organopolysiloxane having silicon-bonded hydrogen atoms and consisting of ingredient (B-1), and in some cases ingredient (B-2) and/or ingredient (B-3) composed of.

Component (B-1) is the main component of component (B), and functions not only as a crosslinking agent but also as an effective interfacial bonding promoter. Component (B) may consist only of component (B-1) as a crosslinking agent. This ingredient contains an organopolysiloxane represented by the following average molecular formula: R ³ ₃ SiO (R ³ ₂ SiO) _j (R ³ H SiO) _k SiR ³ ₃

In this formula, R ³ represents a phenyl group or a methyl group; the methyl group constitutes 90 mol% or more of all groups contained in R ³ . If the content of methyl groups is below the recommended limit, the cured body will acquire color at high temperature. In this formula, "j" is a number ranging from 0 to 35; and "k" is a number ranging from 5 to 100. If the value of "j" exceeds the suggested upper limit, a composition with good joinability will not be provided. If the value of "k" is below the suggested lower limit, a composition with good joinability will not be provided, and on the other hand, if the value of "k" exceeds the suggested upper limit, a cured body with low mechanical strength will be obtained. In addition, the content of silicon-bonded hydrogen atoms should be equal to or greater than 0.5 wt.%. If the content of silicon-bonded hydrogen atoms is below 0.5 wt.%, it will be difficult to provide a composition with good bondability. It is suggested that ingredient (B-1) should be liquid at 25°C and have a viscosity at 25°C in the range of 3 to 10,000 mPa·s, preferably 5 to 5,000 mPa·s. If the viscosity is below the suggested lower limit, this will impair the mechanical and joint strength of the cured body, and on the other hand, if the viscosity exceeds the suggested upper limit, this will impair the processability of the composition.

Ingredient (B-1) can be represented by an organopolysiloxane represented by the average molecular formula given below, wherein Me and Ph are the same as defined above. Me ₃ SiO (MeH SiO) ₁₀ SiMe ₃ Me ₃ SiO (MeH SiO) ₈₀ SiMe ₃ Me ₃ SiO (Me ₂ SiO) ₃₀ (MeH SiO) ₃₀ SiMe ₃ Me ₂ Ph SiO (MeH SiO) ₃₅ SiMe ₂ Ph

Component (B-2) and component (B-3) can be added to component (B-1) to change the physical properties of the composition (B) so as to suit specific usage conditions. Component (B-2) can be added to improve the mechanical strength of the cured body, as well as the aggregation and bonding properties. Component (B-2) contains organopolysiloxane represented by the following average composition formula: (HR ⁴ ₂ SiO _1/2)l (R ⁴ ₃ SiO _1/2 ) _m (R ⁴ ₂ SiO _2/2 ) _n (R ⁴ SiO _3/2 ) _o (SiO _4/2 ) _p (R ⁵ O _1/2 ) _q

In this formula, ^R4 represents phenyl or methyl. The methyl group constitutes 90 mole % or more of all groups contained in R ⁴ . If the content of methyl groups is below the recommended limit, this may cause the cured body to acquire color at high temperature. In the above formula, R ⁵ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. The alkyl group of R ⁵ having 1 to 10 carbon atoms is represented by methyl, ethyl, and isopropyl. In addition, in the formula, "l", "m", "n", "o", "p", and "q" are numerical values representing the ratio of siloxane structural units to hydroxyl or alkoxy groups, and satisfy The following conditions: 0.4 ≤ l ≤ 0.7; 0 ≤ m ≤ 0.2; 0 ≤ n ≤ 0.05; 0 ≤ o ≤ 0.5; 0.3 ≤ p ≤ 0.6; 0 ≤ q ≤ 0.05; and l+m+n+o+p = 1. If the value of "l" is lower than the recommended lower limit, the desired hardness will not be achieved, and on the other hand, if the value of "l" exceeds the recommended upper limit, this will reduce the molecular weight of this ingredient and will not allow sufficient hardness to be imparted to the cured body. Mechanical strength. In addition, if the value of "m" exceeds the recommended upper limit, the desired hardness will not be achieved. If the value of "n" exceeds the recommended upper limit, the desired hardness will not be achieved. If the value of "o" exceeds the suggested upper limit, this will impair the dispersibility of the ingredients and will not allow to impart sufficient mechanical strength to the cured body. If the value of "p" is lower than the recommended lower limit, the desired hardness will not be achieved, and on the other hand, if the value of "p" exceeds the recommended upper limit, this will impair the dispersibility of this ingredient in the composition and will It does not allow to obtain the desired mechanical strength. Finally, if the value of "q" exceeds the suggested upper limit, this will reduce the molecular weight of the ingredients and will not allow to impart sufficient mechanical strength to the cured body. This ingredient should contain at least 0.5 wt.% of silicon-bonded hydrogen atoms. If the content of silicon-bonded hydrogen atoms is below 0.5 wt.%, sufficient mechanical strength cannot be imparted to the cured body. In order to improve the miscibility of this ingredient with the composition, this ingredient should be liquid or solid at 25°C.

Ingredient (B-2) can be represented by organopolysiloxane represented by the average composition formula given below, wherein Me and Ph are the same as defined above. (HMe ₂ SiO _1/2 ) _0.67 (SiO _4/2 ) _0.33 (HMe ₂ SiO _1/2 ) _0.50 (Me ₃ SiO _1/2 ) _0.17 (SiO _4/2 ) _0.33 (HMe ₂ SiO _1/2 ) _0.65 (Ph SiO _3/2 ) _0.05 (SiO _4/2 ) _0.30

Component (B-3) is used to control the hardness of the cured body. This component is an organopolysiloxane represented by the following average molecular formula: HR ⁶ ₂ SiO (R ⁶ ₂ SiO) _r SiR ⁶ ₂ H wherein R ⁶ represents a phenyl group or a methyl group, and wherein the ^methyl group constitutes the At least 90% of all groups. If the content of methyl groups is below the recommended lower limit, this will allow the cured body to acquire color at high temperatures. In the above formula, "r" represents a number ranging from 10 to 100. If "r" is below the suggested lower limit, it will be difficult to provide a cured body with the desired hardness, and on the other hand, if the value of "r" exceeds the suggested upper limit, the cured body will lose its mechanical strength.

Ingredient (B-3) can be exemplified by an organopolysiloxane represented by the following average molecular formula, wherein Me and Ph are the same as defined above: HMe ₂ SiO (Me ₂ SiO) ₂₀ SiMe ₂ H HMe ₂ SiO (Me ₂ SiO) ₈₀ SiMe ₂ H HMe ₂ SiO (Me ₂ SiO) ₅₀ (MePh SiO) ₅ SiMe ₂ H

Component (B) contains 80 to 100 wt.% of component (B-1), 0 to 20 wt.% of component (B-2), and 0 to 10 wt.% of component (B-3), which Expressed as a relative percentage of the total weight of component (B). Preferably, ingredient (B-1) may contain at least 85, 90, or 95 wt.% of component (B). Ingredient (B-2) may be present and included in an amount within a range, wherein the lower end of the range may be 0 wt.%, at least 5, 10, or 15 wt.%, and the upper end of the range is higher than the The lower end of the range, but not more than 5, 10, 15, or 20 wt.% of the total amount of component (B). Ingredient (B-3) may be present and comprises component (B) relative to the remainder of ingredient (B-1 ) and ingredient (B-2). Generally speaking, the amount of component (B-3) is low so that the cured body of the composition of the present invention has sufficient hardness. The composition of component (B) reduces pad fouling due to migration of silicone material onto the pad. Component (B) is liquid at 25°C and has a viscosity in the range of 5 to 100,000 mPa·s, preferably 10 to 50,000 mPa·s, which makes component (B) easy to handle.

Component (B) is added in an amount such that per 1 mol of the total content of alkenyl groups in component (A), there is silicon bonding in the range of 0.5 to 2.0 mol, preferably 0.8 to 1.8 mol A hydrogen atom. If the content of component (B) is lower than the suggested lower limit, or exceeds the suggested upper limit, it will not be able to impart desired hardness, mechanical properties, and bonding properties to the cured body of the composition.

Component (C) is an adhesion promoter. Such adhesion promoters may be those known in the art and are for addition to the hydrosilylation-curable organopolysiloxane composition. Exemplary component (C) is an organosilane or organosiloxane containing epoxy-containing organic groups, alkenyl groups, and silicon-bonded alkoxy groups. Component (C) can be exemplified by the following compounds: organosilane or organosiloxane oligomer, which has 4 to 20 silicon atoms and a linear, branched, or cyclic molecular structure, and contains trialkoxysiloxane (such as trimethoxysilyloxy or triethoxysilyloxy) or trialkoxysilylalkyl (such as trimethoxysilylethyl or triethoxysilylethyl), and hydrogen silyl or alkenyl groups (such as vinyl or allyl); organosilanes or organosiloxane oligomers, which have 4 to 20 silicon atoms and a linear, branched, or cyclic molecular structure, and contain trioxane Oxysiloxy or trialkoxysilylalkyl groups and methacryloxyalkyl groups (such as 3-methacryloxyalkyl); organosilanes or organosiloxane oligomers , which has 4 to 20 silicon atoms and a straight chain, branched chain, or cyclic molecular structure, and contains a trialkoxysilyloxy group or a trialkoxysilyl group, and an alkyl group containing an epoxy group ( Such as 3-glycidoxypropyl (3-glycidoxypropyl), 4-glycidoxybutyl, 2-(3,4-epoxycyclohexyl)ethyl, or 3-(3,4- Epoxycyclohexyl)propyl); the reaction product of aminoalkyltrialkoxysilane and epoxy-bonded alkyltrialkoxysilane; or epoxy-containing ethylpolysilicate. Specific examples are the following compounds: Vinyltrimethoxysilane, Allyltrimethoxysilane, Allyltriethoxysilane, Hydrogentriethoxysilane, 3-Glycidoxypropyltrimethoxysilane , 3-glycidoxypropyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane , 3-methacryloxypropyltriethoxysilane, the reaction product of 3-glycidoxypropyltriethoxysilane and 3-aminopropyltriethoxysilane; 3-epoxy The condensation reaction product of propoxypropyltrimethoxysilane and methylvinylsiloxane oligomer, which is terminated by silanol groups; 3-methacryloxypropyltriethoxysilane and Condensation reaction product of methylvinylsiloxane oligomer terminated with silanol groups; and (3-trimethoxysilylpropyl)isocyanurate.

From the viewpoint of preventing yellowing resistance and lowering of light transmittance, when the cured body is used at elevated temperature for a long time, it is preferable that component (C) does not contain reactive nitrogen atoms such as amine groups. This adhesion promoter is preferably a low viscosity liquid having a viscosity in the range of 1 to 500 mPa·s at 25°C.

Component (C) should be added in an amount that does not impair the curing properties (in particular, does not cause discoloration of the cured body). More specifically, it should be added in an amount of at least 0.01 parts by weight and at most 5 parts by weight, preferably at least 0.1 parts by weight and up to 100 parts by weight of the sum of components (A) and (B). 3 parts by weight more.

Component (D) is a hydrosilylation reaction catalyst, which is used to accelerate the hydrosilylation reaction of the composition. Such catalysts can be exemplified by platinum-based catalysts, platinum-based compound catalysts, metallic platinum catalysts, rhodium-based catalysts, or palladium-based catalysts. From the viewpoint of efficiently accelerating the hydrosilylation reaction of components (A) and (B), thereby accelerating the curing of the composition, it is recommended to use a platinum-based catalyst. Such catalysts can be represented by fine platinum powder, platinum black, chloroplatinic acid, alcohol-modified chloroplatinic acid, diene complexes of chloroplatinic acid, and olefinic complexes of platinum; ester), platinum bis(acetylacetonate), or similar platinum-carbonyl complexes; complexes of chloroplatinic acid and divinyl-tetramethyldisiloxane, chloroplatinic acid and tetravinyl- Complexes of tetramethyl-cyclotetrasilane, or similar complexes of chloroplatinic acid and alkenylsiloxane; complexes of platinum and divinyltetramethyl-disiloxane, platinum and tetrasiloxane Complexes of vinyl tetramethyl-cyclotetrasiloxane, or similar complexes of platinum and alkenyl siloxane; complexes of chloroplatinic acid and ethynyl alcohol, etc. From the standpoint of hydrosilylation efficiency, it is recommended to use complexes of platinum and alkenyl siloxane.

Alkenylsiloxanes are exemplified by the following compounds: 1,3-divinyl-1,1,3,3-tetramethyldisiloxane; 1,3,5,7-tetramethyl-1,3, 5,7-Tetravinylcyclotetrasiloxane; alkenyl siloxane in which a part of the methyl group is substituted by ethyl, phenyl, etc.; or similar substituted alkenyl siloxane oligomers; Or an alkenyl siloxane oligomer, wherein the vinyl group of the alkenyl siloxane is substituted by an allyl group, a hexenyl group, or a similar group. Due to the high stability of the platinum-alkenylsiloxane complex, 1,3-divinyl-1,1,3,3-tetramethyldisiloxane is recommended.

Furthermore, to further improve the stability of platinum-alkenylsiloxane complexes, they can be combined with: 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, 1,3-diallyl-1,1,3,3-tetramethyldisiloxane, 1,3-divinyl-1,3-dimethyl-1,3-diphenyldisiloxane Oxane, 1,3-divinyl-1,1,3,3-tetraphenyldisiloxane, 1,3,5,7-tetramethyl-1,3,5,7-tetravinyl Cyclotetrasiloxane, or similar alkenylsiloxane oligomers or organosiloxane oligomers such as dimethylsiloxane oligomers, especially alkenylsiloxane oligomers.

There is no particular limitation on the usable amount of component (D) provided that it accelerates the curing of the composition. More specifically, it is recommended that component (D) be added in an amount of 0.01 to 500 ppm, preferably 0.01 to 100 ppm, in terms of weight unit, so that the content of platinum-type metal atoms (especially platinum atoms in this component) is 0.01 to 500 ppm. ppm, and more preferably in the range of 0.1 to 50 ppm. If the content of component (D) is below the suggested lower limit, it will be difficult to provide sufficient curing, and on the other hand, if the content of component (C) exceeds the suggested upper limit, this will cause the cured body to acquire color.

In order to improve the handleability and bonding properties of the composition, it may further contain (E) fumed silica having a BET specific area in the range of 20 to 200 m ² /g. This component should be used in an amount of 1 to 10 parts by weight per 100 parts by weight of the sum of components (A), (B), (C), and (D). If component (E) is used in such an amount that its BET specific area is lower or higher than the suggested range, this will impair the processability and will not allow the desired composition viscosity to be obtained. Furthermore, if the content of component (E) exceeds the suggested upper limit, this will impair light transmission properties.

In order to prolong the pot life and storage stability at room temperature, the composition may further have component (F), such as 1-ethynyl cyclohexan-1-ol, 2-methyl-3-butyne -2-ol, 3,5-dimethyl-1-hexyn-3-ol, 2-phenyl-3-butyn-2-ol, or similar acetylenic alcohols; 3-methyl-3-pentene En-1-yne, 3,5-dimethyl-3-hexen-1-yne, or similar enyne compounds; 1,3,5,7-tetramethyl-1,3,5,7- Tetravinylcyclotetrasiloxane, 1,3,5,7-tetramethyl-1,3,5,7-tetrahexenylcyclotetrasiloxane, or similar methylenylsiloxane oligo polymer; dimethylbis(3-methyl-1-butyne-3-oxy)silane, methylvinylbis(3-methyl-1-butyne-3-oxyl)silane, or similar alkynyloxysilanes; benzotriazoles, or similar hydrosilylation inhibitors.

Component (F) is used in an amount sufficient to inhibit gelation or solidification of the composition during mixing of components (A), (B), (C), and (D), and which is required to provide long-term storage of the composition. More specifically, it is recommended to add this component in an amount of 0.0001 to 5 parts by weight, preferably 0.01 to 3 parts per 100 parts by weight of the sum of components (A), (B), (C), and (D). parts by weight.

Within the scope of limitations that do not conflict with the purpose of the present invention, in addition to component (E), the composition may contain other arbitrary components, such as silicon dioxide, glass, zinc oxide, or similar inorganic fillers; polysiloxane rubber powder ; Polysiloxane resin, polymethacrylate resin, or similar resin powder; heat-resistant agents, dyes, pigments, flame retardants, solvents, etc.

From a handling point of view, it is recommended that the composition be a liquid and have a viscosity in the range of 10 to 1,000,000 mPa·s at 25°C. If the composition is intended to be used as a sealing agent for optical semiconductor elements, it has a viscosity at 25°C in the range of 100 to 10,000 mPa·s, and if it is intended to be used as a bonding agent for optical semiconductor elements, it has It has a viscosity in the range of 1,000 to 500,000 mPa·s at 25°C.

The composition is cured by keeping at room temperature or by heating. In order to accelerate curing, it is recommended to cure the composition by heating. The heating temperature should be in the range of 50 to 200°C.

The composition provides excellent joint durability for the following: steel, stainless steel, aluminum, copper, silver, titanium, titanium alloys, or other metals or alloys; silicon semiconductors, gallium phosphide-based semiconductors, gallium arsenide-based semiconductors, based on Semiconductors of gallium nitride, or similar semiconductor elements; ceramics, glasses, thermosetting resins, and thermoplastic resins containing polar groups, and especially if the above objects are subject to heating and cooling cycles.

It is suggested that curing of the composition results in a cured body having a hardness in the range of 30 as measured by a Type D hardness meter according to JIS K 6253, with the upper limit being higher than the lower limit, being at most 60, 65, or 70. If the cured body has a hardness below 30, its cohesion will be poor and its strength and bonding ability will be insufficient, and on the other hand, if the hardness exceeds 70, the cured body will appear brittle and it will not provide sufficient bonding nature. For preferred embodiments, the cured body may have a hardness of at least 40, 50, 55, or 60.

The following are embodiments of the optical semiconductor device of the present invention.

The optical semiconductor device of the present invention includes an optical semiconductor element that is sealed in a housing by a cured body of a sealing material formed from the composition of the present invention, or bonded to a case using a cured body of a bonding material formed from the composition of the present invention. shell. Optical semiconductor devices may include light emitting diodes (LEDs), semiconductor lasers, photodiodes, optoelectronic crystals, solid state image pickup devices, or optocoupler light transmitters and receivers. The most suitable application is LED.

Since in LEDs, light is emitted from semiconductors in vertical and horizontal directions, it is necessary to make components of the device from materials that do not absorb light and have high light transmittance or high light reflectance. Substrates supporting optical semiconductor components are not an exception to this rule. Such substrates can be made of: silver, gold, copper, or another conductive metal; aluminum, nickel, or another non-conductive metal; PPA (polyphthalamide), LCP (liquid crystal polymer), or another thermoplastic resin mixed with white pigment; epoxy resin, BT resin, polyimide resin, silicone resin, or similar thermosetting resin mixed with white pigment; aluminum oxide, aluminum nitride, or the like ceramics. Since the composition of the present invention provides good bonding to the semiconductor element and the substrate, it improves the reliability of the obtained optical semiconductor device.

The optical semiconductor device of the present invention is described in more detail with reference to FIG. 1 . FIG. 1 is a cross-sectional view of a single surface mount LED, which is shown as a general example of an optical semiconductor device. The LED in FIG. 1 includes an LED chip 5 which is die-bonded to a die pad 3 via a bonding material 4 inside a housing 1 made of polyphthalamide resin (PPA). The LED chip 5 is then wire-bonded to the inner lead 2 by the bonding wire 6 , and sealed together with the inner wall of the housing by the sealing material 7 . In the LED of the present invention, the composition used to form the bonding material 4 and/or the sealing material 7 is the curable organopolysiloxane composition of the present invention. example

The curable organopolysiloxane composition of the present invention and the optical semiconductor device of the present invention will be further described in detail with reference to applications and comparative examples. In these applications and comparative examples, the viscosity values correspond to 25°C.

Using the methods described below, the viscosity of the curable organopolysiloxane composition mentioned in the application and comparative examples, and the hardness, light transmittance, and bonding strength of the cured body were measured. [Viscosity of curable organopolysiloxane composition]

Within 30 minutes after preparing the curable organopolysiloxane composition, use a viscometer (AR-550, a product of TA Instrument Co., Ltd.) and use a 2° cone and plate with a diameter of 20 mm to measure This feature. Viscosity was measured at shear rates of 1 sec-1 and 10 sec-1 after first applying a pre-shear. Thixotropy is defined as the shear dependent change in viscosity determined by dividing the viscosity at 1 sec-1 by the viscosity at 10 sec-1. [Hardness of solidified body]

The curable organopolysiloxane was formed into a cured sheet-like body by pressure molding at 150° C. for 1 hour, and the latter was used to measure hardness with a type D durometer according to JIS K 6253. [Light-transmitting properties of the cured body]

The curable organopolysiloxane composition was sandwiched between two glass plates and cured by keeping it at 150°C for 1 hour. The light transmission properties of the obtained cured bodies were measured at 25°C using an automatic recording spectrophotometer (optical path: 0.1 cm) capable of measuring at any wavelength of visible light (wavelength range from 400 nm to 700 nm). The light transmittance through the cured body is determined by subtracting the light transmittance through the glass alone from the light transmittance through the glass and composition. The light transmittance obtained for a wavelength of 450 nm is shown in Table 1. [Device Pad Contamination]

Put a 10 mm × 10 mm square gold wafer and 100 mg curable organopolysiloxane composition in an ampoule, and separate it with a space of about 20 mm, then seal the ampoule and place it in an oven, and heat it from room temperature for 30 minutes up to 170°C, and further kept at 170°C for 30 minutes to cure the organopolysiloxane composition. The discoloration of the gold wafers was visually inspected and scored into four grades, where +++ means highly polluted, ++ means polluted to a certain degree, + means stains can be observed, and no pollution. [Embodiment Examples 1 to 4, Comparative Example 1]

Listed below are the formulas for the ingredients used to prepare the curable organopolysiloxane compositions shown in the application and comparative examples, wherein Vi represents a vinyl group, Me represents a methyl group; Vi% shows the vinyl group in all organic groups Percentage (mole%).

Ingredient (a-1): organopolysiloxane (Vi% = 2.06 mol%) having a viscosity of 60 mPa·s and represented by the following average composition formula: (Me ₂ Vi SiO _1/2 ) _0.042 (Me ₂ SiO _2/2 ) _0.958

Ingredient (a-2): organopolysiloxane (Vi% = 50 mol%) having a viscosity of 4 mPa·s and represented by the following average molecular formula: (MeVi SiO _2/2 ) ₄

Ingredient (a-3): organopolysiloxane (Vi% = 33 mol%) represented by the following average molecular formula: (MeVi SiO _1/2 ) ₄ (SiO _4/2 ) ₁

Ingredient (a-4): organopolysiloxane (Vi% = 5.8 mol%) which is solid at 25°C and represented by the following average composition formula: (Me ₂ Vi SiO _1/2 ) _0.09 (Me ₃ SiO _1/2 ) _0.43 (SiO _4/2 ) _0.48 (HO _1/2 ) _0.03

Ingredient (b-1): organopolysiloxane having a viscosity of 20 mPa·s, containing 1.5 wt.% of silicon-bonded hydrogen atoms, and represented by the following average molecular formula: Me3 SiO (MeH SiO) ₁₀ SiMe ₃

Ingredient (b-2): organopolysiloxane having a viscosity of 120 mPa·s, containing 1.03 wt.% of silicon-bonded hydrogen atoms, and represented by the following average composition formula: (HMe ₂ SiO _1/2 ) _0.67 (SiO _4/2 ) _0.33

Ingredient (c): a condensation reaction product of 3-glycidoxypropyltrimethoxysilane and methylvinylsiloxane oligomer, which is terminated by silanol groups at both molecular ends, and It has a viscosity of 30 mPa·s.

Component (d): 1.3-divinyl-1,1,3,3-tetramethyldisiloxane complex of platinum and 1,3-divinyl-1,1,3,3-tetramethyldisiloxane Methyldisiloxane solution (contains about 4 wt.% platinum metal)

Ingredient (e): Fumed silica having a BET surface area in the range of 190 to 210 m ² /g, and obtained by using hexamethyldisilazane (RX300, ie Nippon Aerosil Co., Ltd. products) surface treated and hydrophobized

Ingredient (f): Hydrosilylation inhibitor alkoxysilane

表2.

產業利用性Using the component ratios shown in Table 1, curable organopolysiloxane compositions were prepared. The properties of the resulting material are described in Table 2. A visual representation of pad contamination is provided in FIG. 2 . Table 1.

Table 2.

Industrial utilization

The curable organopolysiloxane composition of the present invention can be used as a sealant and bonding agent for the following: optical semiconductor elements of LEDs, semiconductor lasers, photodiodes, photoelectric crystals, solid-state image pickup elements, optical couplers transmitter and receiver etc. The optical semiconductor device of the present invention can be used as an optical device, an optical instrument, a lighting device, an illumination device, or a similar optical semiconductor device.

1‧‧‧Shell 2‧‧‧Inner wire 3‧‧‧Chip pad 4‧‧‧Joining material 5‧‧‧LED chip 6‧‧‧Bond wire 7‧‧‧Sealing material

1 is a cross-sectional view of a surface-mounted light emitting diode (LED), which is shown as an example of the optical semiconductor device of the present invention.

Reference Part Numbers Used in Embodiments 1 Case (made of polyphthalamide resin) 2 Inner wire 3 Die pad 4 Bonding material 5 LED chip 6 Bonding wire 7 Sealing material

Figure 2 is a set of photos showing the test results of gold pad contamination.

1‧‧‧Shell

2‧‧‧Inner wire

3‧‧‧Die Pad

4‧‧‧joining materials

5‧‧‧LED chip

6‧‧‧Joining wire

7‧‧‧Sealing material

Claims (7)

A curable organopolysiloxane composition comprising at least the following components: (A) alkenyl-containing organopolysiloxane comprising 15 to 35wt.% of component (A-1) and 65 to 85wt. % of ingredient (A-2), wherein ingredient (A-1) contains organopolysiloxane with the following average composition formula: (R ¹ ₃ SiO _1/2 ) _a (R ¹ ₂ SiO _2/2 ) _b (R ¹ SiO _3/2 ) _c (SiO _4/2 ) _d wherein R ¹ represents phenyl, methyl, or an alkenyl group with 2 to 10 carbon atoms; 0.4 to 50 mole % of all R ¹ groups have Alkenyl groups of 2 to 10 carbon atoms; methyl constituting 90 mole % or more of the sum of methyl and phenyl contained in ^R1 ; "a", "b", "c", and "d" A number that satisfies the following conditions: 0

a

0.05; 0.9

b

1;0

c

0.03;0

d

0.03; and a+b+c+d=1; component (A-2) contains organopolysiloxane with the following average composition formula: (R ² ₃ SiO _1/2 ) _e (R ² ₂ SiO _2/2 ) _f (R ² SiO _3/2 ) _g (SiO _4/2 ) _h (HO _1/2 ) _i wherein R ² represents phenyl, methyl, or alkenyl having 2 to 10 carbon atoms; 5 to 10 molar All ^R2 groups in mole% are alkenyl groups having 2 to 10 carbon atoms; methyl constitutes 90 mole% or more of the sum of methyl and phenyl contained in ^R2 ; "e", "f ", "g", "h", and "i" are numbers satisfying the following conditions: 0.4

e

0.6;0

f

0.05;0

g

0.05; 0.4

h

0.6; 0.01

i

0.05; and e+f+g+h=1; (B) organopolysiloxane containing silicon-bonded hydrogen atoms and comprising 80 to 100 wt.% of component (B-1), 0 to 20 wt.% Component (B-2), and 0 to 10wt.% component (B-3); its amount is such that in the total content of alkenyl in per 1 mol of component (A), there are 0.5 to 2.0 mol Silicon-bonded hydrogen atoms in component (B) within the range wherein component (B-1) comprises an organopolysiloxane containing at least 0.5 wt.% silicon-bonded hydrogen atoms, and is Represented by the following average molecular formula: R ³ ₃ SiO(R ³ ₂ SiO) _j (R ³ HSiO) _k SiR ³ ₃ wherein R ³ represents phenyl or methyl; methyl constitutes 90 moles of all groups contained in R ³ % or more; "j" is a number ranging from 0 to 35; and "k" is a number ranging from 10 to 100; ingredient (B-2) contains organopolysiloxane, which organopolysiloxane Oxanes contain at least 0.5 wt.% of silicon-bonded hydrogen atoms and are represented by the following average composition formula: (HR ⁴ ₂ SiO _1/2 ) _l (R ⁴ ₃ SiO _1/2 ) _m (R ⁴ ₂ SiO _{2 /2} ) _n (R ⁴ SiO _3/2 ) _o (SiO _4/2 ) _p (R ⁵ O _1/2 ) _q where R ⁴ represents phenyl or methyl; methyl constitutes all groups contained in R ⁴ 90 mole% or more of R ⁵ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms; "l", "m", "n", "o", "p", and "q" It is a number that satisfies the following conditions: 0.4

l

0.7;0

m

0.2;0

no

0.05;0

o

0.5; 0.3

p

0.6;0

q

0.05; and l+m+n+o+p=1; component (B-3) is an organopolysiloxane represented by the following average molecular formula: HR ⁶ ₂ SiO(R ⁶ ₂ SiO) _r SiR ⁶ ₂ H where R ⁶ represents phenyl or methyl; methyl constitutes at least 90% of all groups contained in R ⁶ ; and "r" is a number ranging from 10 to 100; (C) an adhesion promoter in an amount per 0.1 to 5 parts by weight in 100 parts by weight of the sum of components (A) and (B); and (D) a hydrosilylation catalyst in an amount sufficient to cure the composition. The curable organopolysiloxane composition according to claim 1, which further comprises: (E) fumed silica, which has a BET specific area of 20 to 200 m ² /g, and is a group of 100 parts by weight It is added in an amount of 1 to 10 parts by weight in the sum of parts (A) to (D). The curable organopolysiloxane composition according to claim 1 or claim 2, which is cured to form a cured body having a D-type durometer hardness in the range of 30 to 70 according to JIS K 6253. The curable organopolysiloxane composition according to claim 3, wherein the cured body has a Type D hardness in the range of 55 to 70 according to JIS K 6253. The curable organopolysiloxane composition according to Claim 1 or Claim 2, which is used as a sealant or bonding agent for optical semiconductor elements. The curable organopolysiloxane composition according to claim 5, wherein the optical semiconductor elements are light emitting diodes. An optical semiconductor device, wherein an optical semiconductor element is sealed and/or bonded using a cured body of the curable organopolysiloxane composition according to claim 1 or any one of claims 2 to 6.

Images